For te-shimatta, I always think of someone who simply couldn’t help themselves and went and….. (insert verb here). So, if you think of someone who meant to bring a box of donuts into the office, but got stuck in traffic and ended up eating the whole box. Japanese could say (食べて)+しまった

You can do the same thing with virtually any verb (飲んでしまった、等）but you can cover many situations by using やってしまった。

I couldn’t find a link to someone using Pandora’s Box as an example for this pattern (ie 開けてしまった or 見てしまいました）, but I think it would be another good example of this pattern.

*[edit] locksleyu wisely left a comment (see below) to point out that this pattern ( ってしまう) is bigger than the example I’ve raised. Indeed, this pattern can capture a few different nuances! The challenge for English speakers is that none of the English translations will ever roll off our tongue quite as smoothly as the Japanese.

Thinking of another example, I remember I was once moved to tears (happy tears) after the one and only time I had ever flown in a helicopter—a Japanese colleague, seeing that I was embarrassed, used this form to note the moment: “感動しちゃった”.

A couple of weeks ago, this clever and funny video from Beppu, in Ōita Prefecture, appeared on youtube. The whole thing is pretty tongue-in-cheek, showing a clearly fictitious amusement park that is one big hot spring ‘in motion’– picture roller coasters with a hot tub in each car. Just the idea of it was funny.

The video takes an interesting turn at the end though– the Mayor of Beppu appears and convincingly promises “if this video gets 1 million views, we will make the Spamusement park a reality!”

After the video hit 1 million views in just four days (not really a stretch for a popular video nowadays), people started asking questions of the mayor– was he serious? Is this something they can really pull off? Is it practical? Even if he’s dreaming of making it a reality, many folks have doubts.